Anal orgasm/Prostate orgasm

Hi everyone, Me and my girlfriend are into a lot of ass play just recently she’s been into doing a lot of stuff to me. We’ve tried pegging a few times, recently we bought a new doc Johnson strapon. Before we tried it we did all the usual stuff, she loosened me up with lots of smaller toys. Then it came to pegging, I was a bit tight at first but after a while I loosened up and managed to take it all which really turned her on, it made her go harder and harder. It felt amazing and the harder she went I could feel myself getting closer to cumming, then came the moment when I orgasmed but then when I looked down I hadn’t ejaculated. It felt amazing but stressed me out a bit can you orgasm and not ejaculate as a guy? Anyone got any stories about orgasming from anal only? Male or female.